Superalloy compositions and articles

Abstract

The addition of small amounts of rhenium, technitium and their mixtures and, optionally erbium, to a nickel based superalloy consisting essentially of 19.3-19.7 weight percent chromium, about 0.5% carbon, about 2.5% iron, the balance essentially nickel, provides enhanced mechanical properties particularly suitable for applications in gas turbine engine components.

I claim: 
     
       1. A superalloy composition consisting essentially of about 19.3 to 19.7% chromium, 0.5% carbon, 2 to 3% iron, and the balance essentially nickel, said composition being free of an amount of aluminum sufficient to form a substantial quantity of Ni-Al-Cr-C eutectic composite, said composition further comprising 0 to 1% erbium and 0.1 to 10 atomic percent of an element selected from the group consisting of rhenium, technetium and mixtures thereof, said superalloy composition having improved mechanical properties independent of directional solidification thereof. 
     
     
       2. A superalloy composition as claimed in claim 1, in which said element is rhenium. 
     
     
       3. A superalloy composition as claimed in claim 2, in which said rhenium is present in about 2 to 10 atomic percent. 
     
     
       4. A superalloy composition as claimed in claim 2, in which said rhenium is present in about 5 to 9 atomic percent. 
     
     
       5. A superalloy composition as claimed in claim 1 in which said element is technetium. 
     
     
       6. A superalloy composition as claimed in claim 1, in which said erbium is present in about 0.2 to 0.7%. 
     
     
       7. A gas turbine engine component made from a superalloy composition as claimed in claim 1 herein.